The present invention relates to environmental damage control, and more particularly to the treatment of waterborne petroleum such as for facilitating collection and recovery thereof.
The advent of supertankers and occurrences of large oil spills in recent history have focused attention on the need for systems rapidly deployable to remote locations in such emergencies, systems that are effective in limiting damage to the environment that would otherwise be caused by the spilled oil.
One method for controlling oil spills involves the application of materials that combine with the oil to produce a substance that is more easily confined and/or collected than untreated oil. Such a material is available as ELASTOL.TM. pulverized polyisobutylene (PIB) from General Technology Applications, Inc., of Manassas, Va. In one known process, the material is mixed with water, and then applied to the spill, using apparatus carried by a watercraft.
A disadvantage of this process is that the watercraft is subject to fouling by oil from the spill.
It has also been proposed to dispense the material in dry form from an airborne vehicle such as a helicopter. However, attempts at such delivery have been heretofore unsuccessful because a large proportion of the material is carried away from the target area by air currents, and a preponderance of the material reaching the target is ineffective because it does not penetrate the oil. This latter condition is exacerbated by the gradual absorption of water into the oil, resulting in submergence of significant portions of the spilled oil below several inches of water.
It is also known to dispense a particulate material such as crushed walnut shells from a hovering platform for abrasively cleaning transmission line tower insulators, as disclosed in my U.S. Pat. No. 4,973,361, and further to dispense a fluidic medium such as firefighting foam from a helicopter-borne dispensing module, as disclosed in my U.S. Pat. No. 4,971,082, which is incorporated herein by this reference. One solution to the problem of dispensing the oil spill treatment material involves dispersing the material, mixed with water, from the helicopter. However, this approach requires the water to be carried by the helicopter, severely limiting the quantity of the treatment material that can be delivered on each flight of the helicopter.
Thus there is a need for a system for treating water-borne spilled oil that does not exhibit the above disadvantages.